Every organization, depending on various factors such as the nature of their business and the data they hold, will have a unique requirement for database backups. Hence, the strategy should be comprehensive, compatible and tailored specifically for these unique requirements. Below are some pointers an effective backup strategy should include:

  • Backup Frequency: The frequency of backups should be decided based on the organization’s Recovery Point Objective (RPO). For a production database, full database backups can be scheduled daily, while differential backups could be done every few hours, and transaction log backups should be performed every few minutes.
  • Storage: Azure Blob storage is highly recommended for storing your backups with its built-in redundancy and high availability.
  • Retention: Azure covers for automated backup retention for 7 to 35 days, depending on the service tier you choose. However, for long term backup storage, Azure Backup can be used to retain backups for years.
  • Security: Always ensure that backups are encrypted. With Azure, you are provided with TDE (Transparent Data Encryption) that secures your data and backups.

Table of Contents

Database Restore Strategy:

For a restore strategy, you should consider, what is known as Recovery Time Objective (RTO). This is the maximum tolerable duration in which the database can be offline. Here are some guidelines that could help with an effective restore strategy:

  • Understand different types of restore: Azure allows Point in Time Restore, Deleted Database Restore and Geo-Restore. Understanding the differences between these is key to optimizing your strategy.
  • Testing: Regular testing of restore processes is vital to ensure data integrity is maintained.
  • Documentation: Detailed and up-to-date documentation on the restore process which could include scripts or Standard operating procedures (SOPs) will ensure accuracy and efficiency.

Backup and Restore Strategy in Azure:

Azure SQL Database provides a plethora of capabilities such as automated backups, Point-in-time restore (PITR), long-term retention (LTR) backups and geo-redundant backups. Here is an overview of Azure’s distinctive features:

  • Automated backups: Azure automatically creates backups of your databases that are retained for seven to 35 days, eliminating the need for manual intervention.
  • Point-In-Time Restore (PITR): This feature allows you to restore your database to any point within the retention period.
  • Long-Term Retention (LTR): This feature allows backups to be retained for up to 10 years following regulatory compliance requirements.
  • Geo-Restore: In the event of a regional outage, this feature allows you to restore a database from a geo-replicated backup.

Conclusion:

The dynamics of the organization and its operations should govern the choice of backup and restore strategy. Azure SQL solution’s automated backups, Point-in-Time restores, long-term retention and geo-restore capabilities offer a robust framework to devise a comprehensive and effective backup and restore strategy, helping to minimize data loss and ensure business continuity.

Practice Test

True or False: Azure SQL Database supports automatic backups.

  • True
  • False

Answer: True

Explanation: Azure SQL Database automatically creates database backups and stores them in read-access geo-redundant storage (RA-GRS).

In Azure, Point In Time Restore allows you to restore your database to any point in time within the ___.

  • A) Last 7 days
  • B) Last 14 days
  • C) Last 30 days

Answer: A) Last 7 days

Explanation: Azure SQL Database’s Point In Time Restore allows you to restore your database to any moment within the last week.

The Long-term backup retention (LTR) feature in Azure SQL Database is available for which deployment options?

  • A) General Purpose/Standard
  • B) Business Critical/Premium
  • C) Both A and B

Answer: C) Both A and B

Explanation: Both General Purpose/Standard and Business Critical/Premium deployment options can use the Long-term backup retention (LTR) feature in Azure SQL Database.

True or False: Azure SQL Managed Instance doesn’t support Point In Time Restore.

  • True
  • False

Answer: False

Explanation: Point In Time Restore is a feature available in both Azure SQL Database and Azure SQL Managed Instance.

Which of the following options allows you to restore a deleted Azure SQL database?

  • a) Point in Time Restore
  • b) Long-term Backup Retention
  • c) Geo-Restore
  • d) All of the above

Answer: c) Geo-Restore

Explanation: Geo-Restore can be used to restore a deleted database to another region if the database was enabled with geo-redundant backups.

True or False: In Azure, the Geo-Restore provides the least Recovery Point Objective (RPO) compared to other restore strategies.

  • True
  • False

Answer: True

Explanation: Geo-Restore does indeed have the highest RPO (1 hour or more) compared to other strategies and hence provides the most data loss in case of a disaster.

True or False: SQL Server Agent jobs and Elastic jobs can also be used for backup operations in Azure SQL Managed Instance.

  • True
  • False

Answer: True

Explanation: Backup operations can be orchestrated using SQL Server Agent jobs in Managed Instance and Elastic jobs in Azure SQL Database.

In Azure SQL Database, backup data is retained for how long by default?

  • A) 7 days
  • B) 14 days
  • C) 35 days

Answer: A) 7 days

Explanation: By default, Azure SQL Database retains full backup data for a week.

True or False: Managed Instance backups can also be restored to SQL Server instance on-premises.

  • True
  • False

Answer: False

Explanation: Managed Instance backups are stored in Azure Blob Storage and can’t be restored on-premises SQL Server.

Active Geo-Replication method for Azure SQL Database provides which of the following?

  • A) Redundant copies of data
  • B) Disaster recovery
  • C) Critical workload data protection
  • D) All of the above

Answer: D) All of the above

Explanation: Active Geo-Replication provides protection for critical workload data, supports disaster recovery, and offers redundant copies of data.

True or False: Point-in-time restore allows you to restore a database to a specific time in past from a backup.

  • True
  • False

Answer: True

Explanation: This statement is true, Point-in-time restore allows you to restore data to a specific time in the past from a backup.

A backup captured during the active geo-replication process contains changes from RIP updates.

  • A) True
  • B) False

Answer: B) False

Explanation: During Active Geo-Replication, there are no backups taken, it is a real-time transactional replication.

In SQL Server backup strategy, the transaction log backups depend on differential backups.

  • A) True
  • B) False

Answer: B) False

Explanation: Transaction log backups are independent of the differential backups, and can occur more frequently.

The maximum retention period for automated backups in Azure SQL Database is 35 days.

  • A) True
  • B) False

Answer: A) True

Explanation: The maximum period for retaining automated backups in Azure SQL Database is 35 days.

To perform a backup of an Azure SQL Database, you must stop all the activities on the database you are backing up.

  • A) True
  • B) False

Answer: B) False

Explanation: Azure SQL Database supports online backups, which means that you can continue working on your database while the backup is being performed.

Interview Questions

Why is it important to regularly backup your Azure SQL database?

Regularly backing up your Azure SQL database is important to prevent data loss in case of a system failure, accidental deletion, or any other unforeseen event. It also helps to meet compliance and regulatory requirements.

What is the Point-in-time Restore (PITR) in Azure SQL database?

Point-in-time Restore (PITR) in Azure SQL Database is a self-service capability, which allows you to restore a database from a backup to any point in time during the retention period. It’s very effective in recovering from accidental deletions or modifications in the database.

Which types of backups are automatically taken by Azure SQL Database?

Azure SQL Database automatically creates Full, Differential, and Transaction Log backups. Full backups occur weekly, differential backups occur every 12 hours, and log backups occur every 5-10 minutes.

How can you restore a deleted Azure SQL database?

A deleted Azure SQL database can be restored using the Azure portal, Azure CLI, or PowerShell. The database can be restored to any available service tier within the database’s point-in-time restore (PITR) period.

What is the retention period for Azure SQL Database backup?

Azure SQL Database retains backups for seven to 35 days, depending on the service tier and whether you have configured long-term retention.

What is an active geo-replication in the context of Azure SQL Database?

Active Geo-replication is an Azure SQL Database feature that allows you to create readable secondary databases in the same or different data center (region). This is useful for load balancing and for ensuring business continuity if a catastrophic event occurs at the primary region.

Can Azure SQL Database backups be used to restore data to a point before creation?

No, Azure SQL Database backups cannot restore data to a time before the backup was created. The backups work on a timeline starting from their creation and can restore data to any point on this timeline.

What is Long-term backup retention (LTR) in Azure SQL Database?

The Long-term backup retention (LTR) feature in Azure SQL Database enables you to automatically retain database backups in Azure Blob storage for up to 10 years. This can help you comply with compliance and regulatory requirements.

What is an Azure SQL Database Failover group?

An Azure SQL Database Failover Group is a container for replicating databases between two different Azure SQL Database servers to support failover in case of an outage.

Can you manually initiate a backup of Azure SQL Database?

No, you cannot manually initiate a backup in Azure SQL Database. Azure SQL Database automatically creates and maintains backups for you.

What is the default backup retention period for a Basic service tier Azure SQL Database?

The default backup retention period for a Basic service tier Azure SQL Database is 7 days.

How often does Azure SQL Database take full backups?

Azure SQL Database automatically takes a full backup once a week.

In case of an accidental data deletion, what is the recommended restore strategy?

The recommended restore strategy in case of accidental data deletion is performing a Point-in-Time Restore to restore the deleted data, as this can restore the database to an instance before the deletion occurred.

How does Azure SQL Database guarantee data durability?

Azure SQL Database automatically creates multiple copies of your database in different physical locations to guarantee data durability. If one copy is unavailable or lost, the system switches to another copy of the database.

How can you verify that your backups are being properly maintained in Azure SQL Database?

You can verify that your backups are being properly maintained in Azure SQL Database by performing test restores. This involves restoring the database to a test server and checking that the data is correct and intact.

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